MOSCOW, June 17 (Reuters) - Two Russian state television journalists were killed in Ukraine when they were shelled in clashes between Ukrainian forces and pro-Russian separatists near the eastern city of Luhansk, the Rossiya-24 channel said on Tuesday.

Sound engineer Anton Voloshin was killed at the scene and correspondent Igor Kornelyuk died in hospital after they came under fire while covering fighting in Ukraine’s easternmost province, near the border with Russia, it said on its website.

The Russian Foreign Ministry said the death demonstrated the “criminal nature” of Ukraine’s military operation against pro-Russian rebels and urged authorities in Kiev to investigate.

The Organisation for Security and Cooperation in Europe (OSCE), whose special monitoring Mission is working in eastern Ukraine, echoed the call for a probe into the attack.

“This death is yet another horrid reminder that not enough is being done to protect journalists who risk their lives reporting from conflict zones in Ukraine,” Dunja Mijatovi, the OSCE representative on media freedoms, said in a statement.

A third member of the Russian TV crew, cameraman Viktor Denisov, survived the attack on the rebel roadblock where they were filming.

The crack of heavy artillery and Denisov’s ragged breathing is audible on the shaky footage he shot of the scene, crouched by a military vehicle. As smoke clears, a fighter is shown dragging a wounded man off the road into the bushes.

“I got lucky,” Denisov told the Russian LifeNews website. “One of the shells landed on them ... I ran the other way when the area came under fire.”

A spokeswoman for separatists in Luhansk said the body of Voloshin, who was initially reported missing by Rossiya-24, had been found at the scene.

“His body, or rather, his remains were found directly at the site of the mortar attack in the village of Metalist,” the spokeswoman was quoted by Russian news agencies as saying.

The crisis in Ukraine erupted late last year when protesters took to the streets against a president sympathetic to Moscow. He was overthrown in February, Russia annexed the Crimea region in March and the uprising in the Russian-speaking east began in April.

After his election at the end of May, President Petro Poroshenko ordered a military push to retake territory controlled by rebels.

Kiev says 125 Ukrainian service personnel have been killed. Scores of rebel fighters have also died, as well as an unknown number of civilians.

Last month, an Italian photographer and his Russian translator were killed by mortar fire. (Reporting by Alessandra Prentice in Donetsk, Ukraine, and Alissa de Carbonnel in Moscow; Editing by Kevin Liffey and Sonya Hepinstall)